Preparation with seeding of polymers insoluble in their monomeric compositions

ABSTRACT

Vinyl based polymers and copolymers and method for the preparation of same by first preparing a seeding latex by polymerization in fine suspension of monomers or comonomers having a vinyl base, preferably vinyl chloride, with an excess amount of organo-soluble catalyst and dispersing the seeding latex in monomers or comonomers having the vinyl base to form a polymerizing composition which is polymerized by heating.

D United States Patent 1 [111 3,725,367 Kemp [4 1 Apr. 3, 1973 541PREPARATION WITH SEEDING 0F 3,458,467 7/1969 Herrle et a1 ..260/92.8 wPOLYMERS INSOLUBLE IN THEIR 2,961,432 11/1960 Fikentscher et al...260/92.8 R MONOMERIC COMPOSITIONS 3,370,105 2/1968 De Bell et a1..260/884 3,544,280 12/1970 Thomas ..260/92.8 R [75] In Thomas p,92-B0is-C0l0mbes, 3,522,227 7/1970 Thomas ..260/92.8 R France 3,397,1658/1968 Goodman et a1. 260/879 [73] Assigneez Produits Chimiquespechinersainb 3,373,228 3 1968 Glazer et al. ..260/884 Gobain,Neuillv-sur-Seine, France FOREIGN PATENTS OR APPLICATIONS Filed: y 15,1970 557,663 6/1957 Belgium "260/928 w [21] Appl. No.: 37,852

Primary Examiner-Joseph L. Schofer Assistant Examiner-A. Holler Foreignpp Data Attorney-McDougall, Hersh & Scott May 19, 1969 France ..6916089[57] ABSTRACT [52] U.S. Cl ..260/80.81, 260/87.l, 260/875 C, vinyl basedpolymers and copolymers and method for 6 260/875 R, 260/877, 260/928 N,260/8 the preparation of same by first preparing a seeding 260/884 latexby polymerization in fine suspension of [51] Int. Cl. ..C08f 1/11, C08f1/13, C08f 15/00 monomers or comonomers having a vinyl base [58] MSearch 260/878 80'81 preferably vinyl chloride, with an excess amount ofor- References Cited gano-soluble catalyst and dispersing the seedinglatex Benetta et a1 ..260/92.8 W

5/1968 Smith ..260/92.8 W

in monomers or comonomers having the vinyl base to form a polymerizingcomposition which is polymerized by heating.

28 Claims, No Drawings PREPARATION WITH SEEDING F POLYMERS INSOLUBLE INTHEIR MONOMERIC COMPOSITIONS This invention relates to vinyl basedpolymers and copolymers which are insoluble in their monomeric orcomonomeric compositions and to a process for the preparation of samewith a seeding mixture.

It is an object of this invention to produce and to provide a method forproducing polymers or copolymers based upon a vinyl monomer, preferablyvinyl chloride, having a narrow granular distribution within the rangeof to 50 microns and preferably to 40 microns.

The objects of this invention reside in a process for dispersing, infinely divided form, an aqueous seeding latex of a polymer or copolymerpreviously prepared by polymerization or copolymerization in finesuspension and containing at least a catalyst of the organo-solubletype, in a monomeric or comonomeric composition having a vinyl base, andpreferably vinyl chloride, and then polymerizing the composition.

In anadvantageous modification of the process of this invention, afterthe preparation of the aqueous seeding latex, a finely divideddispersion thereof in the monomeric or comonomeric composition, basedupon vinyl chloride, is achieved and then the prepared reactioncomposition is subjected to polymerization with agitation at moderatespeed.

Use is made of a seeding latex containing to 48 percent by weight andpreferably to percent by weight of the polymer or copolymer particles,in which the polymer copolymer particles have a diameter within therange of 0.03 to 4 microns and preferably 0.1 to 2 microns.

Preparation of the aqueous seeding latex in fine suspension makes use ofwater, a monomeric or comonomeric composition of the vinyl type,preferably vinyl chloride, a dispersing agent and at least one catalystof the organo-soluble type. The concentration of the monomeric orcomonomeric composition is generally within the range of 20 to percentand preferably within the range of 40 to 45 percent by weight based uponthe entire quantity of the reaction mixture. The organic composition isfinely dispersed in water by means of vigorous shearing action, such asobtained for instance by a homogenizer operating under high pressure ora turbine rotating at high speed. The fine suspension is heated underautogenous pressure and under moderate agitation at a temperature whichdepends upon the characteristics of the product which is desired to beobtained.

At the end of the polymerization, heating is discontinued andunconverted monomer or monomers are removed by vaporization ordegassing.

As the dispersing agent, use can be made of one or more protectivecolloids or one or more emulsifiers in an amount within the range of 0.2to 5 percent and generally within the range of 1 to 3 percent by weight,based upon the weight of monomer or comonomer. The protective colloidsare selected of those usually employed in fine suspensionpolymerization, such for example as polyvinyl alcohol, methyl cellulose,carboxy cellulose and gelatin. The emulsifiers of the anionic type canbe represented by the alkylarylsulfonates, alkylsulphates and fatty acidsalts of alkali metals. Such emulsifiers may be used alone or incombination one with another or with emulsifiers of the non-ionic type,

such as fatty alcohols or polyoxyethylened alkylphenols.

A catalyst of the organo-soluble type capable of being used can berepresented by organic peroxides, such as lauroyl peroxide, tertiobutyldiethylperucetatc, diethylhcxylpercarbonate or diacetyl peroxide.

The catalyst or catalysts are employed in relatively high concentrationsof between 0.5 to 5 percent by weight based upon the monomeric orcomonomeric composition, so that, at the end of the preparation of theseeding latex, a sufficient quantity of catalyst will remain to initiatethe polymerization reaction in accordance with the practice of thisinvention.

In the polymerization embodying the features of this invention, use ismade of a seeding latex containing an amount of polymer orcopolymer-within the range of l to 20 percent and preferably within therange of 2 to 6 percent by weight based upon the monomeric orcomonomeric composition. The monomeric or comonomeric compositions usedin the preparation of the seeding latex are selected in the same groupas those polymerized in accordance with the practice of this invention.

According to this invention, the polymer or copolymer formed isinsoluble in the initial monomeric or comonomeric medium.

In accordance with the practice of this invention, the polymerizationprocess is applicable to reaction medium formed of vinyl chloride alone;of vinyl chloride and at least one olefin such as ethylene, propylene,butene-l butene-2, isobutene and methyl-4-pentene-l; of vinyl chlorideand vinyl acetate; of vinyl chloride, vinyl acetate and at least oneolefin as defined above; of vinyl chloride and vinylidene chloride andother compounds,

provided that the copolymers formed are essentially insoluble in theinitial monomeric compositions.

The following examples are given by way of illustration, but not by wayof limitation, of the various comonomeric compositions which may becopolymerized in accordance with the practice of this invention:

comonomeric compositions based on vinyl chloride and at least oneolefin, as defined above, in which the olefin is present in an amountwithin the range of 0.1 to 30 percent by weight and preferably 0.1 to 10percent by weight of the comonomeric composition;

comonomeric compositions based upon vinyl chloride and vinyl acetatecontaining vinyl acetate within the range of 0.1 to 30 percent andpreferably 0.1 to 15 percent by weight of the comonomeric composition;

comonomeric compositions based upon vinyl chloride and vinylidenechloride in which the vinylidene chloride is present in an amount withinthe range of 0.1 to 30 percent by weight and preferably 0.1 to 20percent by weight of the comonomerlc composition.

For a good application of the polymerization process of this invention,there is introduced into the reaction medium with the agency of theseeding latex and/or the monomeric or comonomeric composition, dependingon its solubility, a dispersing agent of the emulsifying or protectivecolloid type in an amount less than 2 percent and preferably in anamount within the range of 0.1 to

0.3 percent by weight based upon the monomeric or comonomericcomposition.

Among the emulsifiers capable of being used, the following are given byway of illustration, namely emulsifiers:

of the anionic type such as sulfonate alkali salts having the generalformula:

in which R and R are aliphatic chains having between 1 and 20 carbonatoms such as methyl, ethyl, propyl, butyl, pentyl, octyl, decyl,octadecyl and the like, and n is between 2 and 6, or sulphosuccinatealkali salts having the general formula: I

in which R and R are aliphatic chains having from 3 to 15 carbon atomssuch as propyl, butyl, hexyl, pentylhexyl, decyl, dodecyl, octadecyl andthe like;

of the non-ionic type such as ethylene polyoxide grafted by styrene orvinyl acetate or fatty acid polyethoxyesters having the general formula:

in which R is an aliphatic chain having from 5 to 20 carbon atoms suchas pentyl, octyl, decyl, dodecyl, octadecyl and the like, and n isbetween and 150. The emulsifiers, as described above, can be used aloneor in various admixtures.

Among the protective colloids capable of being used, reference can bemade by way of example to methyl cellulose, polyvinyl alcohol, carboxycellulose and gelatins.

In order to improve the activity of the organo-soluble catalyst orcatalysts, it may also be advantageous to introduce into the reactionmedium a water soluble activator, such for example as ammonia, sodiumsulphoxylate-formaldehyde, sodium metabisulphite with the seeding latex,or an organo-soluble activator such for example as ascorbyl palmitate orhydroxymaleic acid, with the monomeric or comonomeric composition. Anysuch activator is used in molar dosages generally less than one basedupon the catalyst or catalysts of the organo-soluble type contained inthe particles of the seeding latex.

The dispersion of the seeding latex is achieved by an appropriateagitation means, and preferably with drastic agitation to provide forfiner dispersions. As drastic dispersion means, reference can be made tohomogenizers operating under high pressure or turbines rotating at highspeed. Dispersion means operating at moderate speed may also beemployed.

The polymerization reaction of this invention can be carried out over awide temperature range, generally within the range of 1 to 90 C. andpreferably within the range of 30 to 70 C.

When the reaction medium is raised to the selected polymerizationtemperature, the unused organo-soluble catalyst or catalysts in theparticles of the seeding latex initiate the polymerization of themonomeric or comonomeric composition in the interior of the dropletsuntil the polymeric or copolymeric particle content reaches a value inthe range of about 50 percent by weight, at which time a coagulation ofthe particles occurs within each droplet, and then at the exterior ofsaid droplets without the formation of new particles other than thoserepresented by the droplets initially dispersed. Once the coagulation ofthe polymeric or copolymeric particles is achieved within the droplets,it becomes also possible to continue the polymerization at lowtemperature.

The granular size of the end polymer is directly related to the finenessof the initial dispersion of the seeding latex and the number ofdroplets. Nevertheless, during the course of the polymerization,agglomerations may occur between particles with the result that thefinal granular size is generally higher than that which might beexpected. The kind of catalyst, additive, agitation as well aspolymerization temperature influence the agglomeration.

In some cases, the amount of the organo-soluble catalyst or catalystswithin the particles of the seeding latex is sufficient for thepolymerization of the monomeric or comonomeric compositions to proceedup to a conversion rate above percent without the addition of catalyst.

Generally, however, when a small amount of seeding latex is used or whenthe latter is only sparingly rich in organo-soluble catalyst,polymerization will case before the conversion rate has reached 70percent. Continuation of the polymerization reaction can thereafter beobtained by further addition of one or more organosoluble catalysts.illustrative of the catalysts which can be used for this purpose areisopropyl peroxidicarbonate, acetylcyclohexane-sulphonyl peroxide orlauroyl peroxide. In order to obtain the homogeneity in distribution, itis desirable to effect catalyst addition while the reaction medium isstill liquid, that is to say, before its polymer or copolymer contenthas reached a value within the range of 25 percent by weight. In spiteof this catalyst addition, polymerization proceeds only by addition tothe already existing granules.

At the end of the polymerization, and after degassing to removeunreacted monomer, the polymer is sub jected to a drying operation toeliminate the small quantity of contained water derived from the seedinglatex.

One of the noticeable advantages of the process of this invention is theparticularly small amount of encrustation formed on the walls of thereactor. This can be attributed to the absence of free catalyst in theorganic phase in contact with the walls during at least a part of thepolymerization.

. Patentable invention is also believed to exist in the polymers andcopolymers that are formed, essentially of the vinyl type, which areinsoluble in their monomeric or comonomeric compositions and which arecharacterized by a very narrow distribution range of between 10 and 50microns and more preferably between 20 and 40 microns in diameter.

When the polymerization is achieved at a temperature within the range of50 to 70 C, the compact granules of polymer or copolymer obtained can beused advantageously as a fluidizer of plastisols. Effectively, withregard to fluidizers generally employed, prepared by the process ofemulsion polymerization and copolymerization, it affords the advantageof being lower in cost. By reason of its very great fineness, it doesnot decant in the plastisols. Amounts ranging from to 50 percent byweight, based on the entire quantity of polymer or copolymer used in theplastisols, may be used in place of polymers or copolymers forplastisols prepared by polymerization in emulsion in order to obtainplastisols exhibiting improved rheological properties.

The following examples a re given by way of illustration, but not by wayof limitation, of the practice of this invention:

EXAMPLE 1 Preparation of the seeding latex Into an autoclave of 120liter capacity, there are introduced 55 kg of vinyl chloride, 2.25 kg oflauroyl peroxide, 0.9 kg of sodium dodecylbenzenesulphonate and 55 kg ofwater. At room temperature, a succinct dispersion of the organic phaseinto the aqueous phase is achieved by agitation with a propeller mixerrotating at 100 r.p.m. This predispersion is processed through ahomogenizer, commercially available under the name Manton GaulinHomogenizer under a pressure of 200 bars to obtain a fine suspension.The fine suspension is introduced into an autoclave of 120 litercapacity equipped with a propeller mixer rotating at 50 r.p.m. and isheated to 40 C under autogenous pressure. After pressure drop, that isto say, after about 6 hours, the heating is discontinued and theunreacted vinyl chloride is degassed. There is obtained a latexcontaining 46 percent by weight of polyvinyl chloride, the particles ofwhich have an average diameter of 0.2 micron.

Polymerization according to the process of this invention Into anautoclave of 1,000 liter capacity, there are introduced 60 liters of theabove seeding latex and 500 kg of vinyl chloride in which 1 kg of sodiumoctylsulphosuccinate has previously been dissolved. The seeding latex isdispersed into the monomer at room temperature by a standard typeagitation means in the form of a turbine rotating at 2,900 r.p.m. for 1hour. This dispersion is then transferred into a vertical autoclavehaving a capacity of 1,000 liters and equipped with a ribbon typeagitator rotating at 100 r.p.m. Polymerization is carried out at atemperature of 60 C. The reaction lasts 10 hours until the pressurebegins to drop. After degassing and drying, there is obtained 410 kg ofa polymer, the granules of which have a diameter between and 30 micronsand which are charac terized by properties as set forth in the followingtable:

TABLE 1 Properties Product Example 1 Apparent bulk density (g/cm) 0.45Viscosity index AFNOR according to the standard specification NFT 51013105 Average diameter of the granules (microns) This polymer representsan excellent fluidizer for plastisols.

When 20 parts by weight of the polymer is mixed with 40 parts by weightof a polymer for plastisols, such as obtained by emulsion polymerizationand marketed under the trade name LUCOVYL PE 1801, and 40 parts byweight of dioctylphthalate, there is obtained a plastisol the viscosityof which measures 3,000 centipoises at 25 C when measured by means of aviscometer commercially known under the trade name Drage viscometer."

When 30 parts by weight of this polymer is mixed with 30 parts by weightof the LUCOVYL PE 1801 and 40 parts by weight of dioctyl phthalate,there is obtained a plastisol having a viscosity of 4,000 centipoisesalt 25 C when measured by the Drage viscometer.

By way of comparison, when 60 parts by weight of LUCOVYL PE 1801 ismixed with 40 parts by weight of dioctylphthalate, there is obtained aplastisol having a viscosity of 5,000 centipoises when measured at 25 Cwith a Drage viscometer.

EXAMPLE 2 Preparation of the seeding latex Into an autoclave of 120liter capacity, there are introduced 45 kg of vinyl chloride, 0.9 kg ofsodium dodecylbenzene sulphonate and 55 kg of water and, at roomtemperature, a dispersion of the organic phase into the aqueous phase isachieved by a standard type agitation using a turbine rotating at 2,900r.p.m. for 1 hour to yield a fine suspension. The said fine suspensionis introduced into an autoclave of 120 liter capacity, equipped with apropeller mixer rotating at 50 r.p.m. and then the mixture is heated at46 C under autogenous pressure. After the pressure drop, that is to say,after about 6 hours, heating is discontinued and unreacted vinylchloride is degassed. A latex is obtained containing 46% by weight ofpolyvinyl chloride, the particles of which have an average diameter of0.6 micron.

Polymerization according to the process of this invention Into anautoclave of 1,000 liter capacity, there are introduced 15 liters of theabove seedling latex to which there has been added cm of concentratedammonia and 500 kg of vinyl chloride in which 1 kg of sodiumoctylsulphosuccinate has been dissolved. While at room temperature thereis achieved a dispersion of the seeding latex into the monomer by meansof a turbine rotating at 2,900 r.p.m. for 1 hour. This dispersion istransferred into a horizontal autoclave having a capacity of 1,000liters and equipped with a gate paddle agitator rotating at 50 r.p.m.Polymerization is carried out at a temperature of 50 C. After 4 hoursthe reaction stops at a conversion rate of vinyl chloride of about 10percent. Into the still liquid reaction medium, there is introduced 250grams of isopropyl peroxidicarbonate. The reaction renews and continuesfor 6 hours until pressure begins to drop. After degassing and drying,there is obtained 380 kg of a polymer, the granules of which have adiameter within the range of 20 to 30 microns and properties as setforth in the following table:

TABLE II Product of Example 2 0.42

Preparation of the seeding latex The seeding latex in the mannerdescribed in Example 2.

is prepared Copolymerization representing the practice of this inventioninto an autoclave of 1,000 liter capacity, there are introduced litersof the above seeding latex, lOO cm of concentrated ammonia and a mixtureof 465 kg of vinyl chloride and 35 kg vinyl acetate in which 1 kg ofsodium octylsulphosuccinate has previously been dissolved. The seedinglatex is dispersed in the monomeric composition at room temperature bythe use of a standard type agitation means in the form of a turbinerotating at 2,900 r.p.m. for 1 hour. This dispersion is transferred intoa vertical autoclave of 1,000 liter capacity, equipped with a ribbontype agitator rotating at 100 r.p.m. Polymerization is carried out at atemperature of 60 C, corresponding to a relative pressure of nine bars.After 4 hours, the reaction stops at a conversion rate of monomer ofabout 10 percent. Into the still liquid reaction medium, introduction ismade of 100 grams of isopropyl peroxidicarbonate and 180 grams oflauroyl peroxide. The reaction is renewed and continues for 6 hours.After degassing and drying, there is obtained 400 kg of a copolymer, thegranules of which have a diameter within the range of to 60 microns andwhich are characterized by properties as set forth in the followingtable:

TABLE III Properties Apparent bulk density (g/cm) Viscosity index AFNORaccording to the standard specification Product Example 3 0.48

This copolymer is an excellent fluidizer for plastisols and is notdetrimental to their gelation ability.

When used herein to define the amounts of various of the ingredients,the term monomer and comonomer compositions is meant to refer to themonomer or comonomer in the absence of any diluents.

It will be understood that changes may be made in the details offormulation and operation without departing from the spirit of theinvention, especially as defined in the following claims.

Iclaim:

1. In a process for the preparation of polymers and copolymers having avinyl base, the steps of dispersing into the organic vinyl basedmonomeric system a seeding latex containing to 48 percent by weight ofthe vinyl based polymer containing organo soluble catalyst in excess ofthe amount required to form the seed polymer, whereby the seeding latexforms the dispersed phase and the organic monomeric system thecontinuous phase in which the amount of polymer of the seeding latexdispersed in the monomeric system is within the range of l-20 percent byweight of the monomer, heating the composition to polymerizationtemperature whereby polymerization proceeds initially in the interior ofthe droplets, coagulating the polymer within the droplets, andcontinuing the polymerization externally of the droplets.

2. A process for the preparation of polymers and copolymers having avinyl base asclaimed in claim 1 in which the seeding latex is preparedby polymerizing in fine suspension monomers or comonomers having a vinylbase with an amount of organo-soluble catalyst in excess of thatrequired to polymerize the monomer to form an aqueous seeding latex inwhich the polymer or copolymer particles contain excess catalyst of theorgano-soluble type and are present in an amount of at least 30 percentby weight of the latex.

3. The process as claimed in claim 2 in which the vinyl base material isvinyl chloride.

4. The process as claimed in claim 2 in which the polymerizingcomposition is subjected to polymerization under relatively mildagitation.

5. The process as claimed in claim 2 in which the amount of polymer orcopolymer in the seeding latex is within the range of 40 to 45 percentby weight.

6. The process as claimed in claim 2 in which the polymer or copolymerparticles of the seeding latex have a diameter within the range of 0.03to 4 microns.

7. The process as claimed in claim 2 in which the polymer or copolymerparticles of the seeding latex have a diameter within the range of 0.1to 2 microns.

8. The process as claimed in claim 2 in which the amount oforgano-soluble type of catalyst introduced with the monomers orcomonomers used for preparing the seeding latex is within the range of0.5 to 5 percent by weight based upon the monomeric or comonomericcomposition.

9. The process as claimed in claim 2 in which the organo-solublecatalyst used in the preparation of the seeding latex is an organicperoxide catalyst.

10. The process as claimed in claim 9 in which the catalyst is selectedfrom the group consisting of lauroyl peroxide, tertiobutyldiethylperacetate, diethylhexylpercarbonate and diacetyl peroxide.

11. The process as claimed in claim 2 in which the amount of polymer orcopolymer of the seeding latex dispersed with the monomer or comonomerof the polymerizing composition is within the range of 2 to 6 percent byweight of the monomer or comonomer of the polymerizing composition.

12. The process as claimed in claim 2 in which a dispersing agent isintroduced in the polymerization composition via the seeding latex, orwith the monomer or comonomers into which the latex is dispersed.

13. The process as claimed in claim 12 in which the dispersing agent isof the emulsifying type. i

14. The process as claimed in claim 12 in which the dispersing agentcomprises a protective colloid.

15. The process as claimed in claim 13 in which the dispersing agent isan anionic agent selected from the group consisting of alkali metalsulphonates and sulphosuccinates.

16. The process as claimed in claim 13 in which the dispersing agent isof a non-ionic type selected from the group consisting of ethylenepolyoxide grafted by styrene or vinyl acetate, or a fatty acidpolyethoxyester.

17. The process as claimed in claim 12 in which the dispersing agent ispresent in an amount less than 2 percent by weight of the monomeric orcomonomeric polymerizing composition.

18. The process as claimed in claim 12 in which the dispersing agent ispresent in an amount within the range of -1 to 0.3 percent by weight ofthe monomer or comonomers of the polymerizing composition.

19. The process as claimed in claim 14 in which the protective colloidis selected from the group consisting of methyl cellulose, polyvinylalcohol, carboxy cellulose and gelatin.

20. The process as claimed in claim 2 in which the monomers andcomonomers polymerized are selected from the group consisting of vinylchloride; vinyl chloride and at least one olefin; vinyl chloride andvinyl acetate; vinyl chloride, vinyl acetate and at least one olefin;vinyl chloride and vinylidene chloride.

21. The process as claimed in claim 20 in which the olefin is selectedfrom the group consisting of ethylene, propylene, butene-l, butene-2,isobutene, and methyl- 4-pentene-l.

22. The process as claimed in claim 2 in which an activator isintroduced via the seeding latex or with the monomer or comonomer intowhich the latex is dispersed.

23. The process as claimed in claim 22 in which when the activator isintroduced via the seeding latex it is selected from the groupconsisting of ammonia, sodium sulphoxylate formaldehyde and sodiummetabisulphite and when the activator is introduced with the monomer orcomonomer it is selected from the group consisting of ascorbyl palmitateand hydroxymaleic acid.

24. The process as claimed in claim 22 in which the activator is used inmolar dosages less than 1 based upon the catalyst or catalysts of theorgano-soluble type contained in the particles of the seeding latex.

25. The process as claimed in claim 2 in which'the amount of catalystcontained in the particles of the seeding latex is sufficient forpolymerization of the monomeric or comonomeric materials to a conversionrate in excess of percent.

26. The process as claimed in claim 2 in which the polymerizingcomposition is heated to a temperature within the range of 1 to C forpolymerization.

27. The process as claimed in claim 2 in which the polymerizingcomposition is heated to a temperature within the range of 30 to 70 Cfor polymerization.

28. The process as claimed in claim 1 in which the polymer is coagulatedwithin the droplets when the polymer particle content is about 50% byweight.

2. A process for the preparation of polymers and copolymers having avinyl base as claimed in claim 1 in which the seeding latex is preparedby polymerizing in fine suspension monomers or comonomers having a vinylbase with an amount of organo-soluble catalyst in excess of thatrequired to polymerize the monomer to form an aqueous seeding latex inwhich the polymer or copolymer particles contain excess catalyst of theorgano-soluble type and are present in an amount of at least 30 percentby weight of the latex.
 3. The process as claimed in claim 2 in whichthe vinyl base material is vinyl chloride.
 4. The process as claimed inclaim 2 in which the polymerizing composition is subjected topolymerization under relatively mild agitation.
 5. The process asclaimed in claim 2 in which the amount of polymer or copolymer in theseeding latex is within the range of 40 to 45 percent by weight.
 6. Theprocess as claimed in claim 2 in which the polymer or copolymerparticles of the seeding latex have a diameter within the range of 0.03to 4 microns.
 7. The process as claimed in claim 2 in which the polymeror copolymer particles of the seeding latex have a diameter within therange of 0.1 to 2 microns.
 8. The process as claimed in claim 2 in whichthe amount of organo-soluble type of catalyst introduced with themonomers or comonomers used for preparing the seeding latex is withinthe range of 0.5 to 5 percent by weight based upon the monomeric orcomonomeric composition.
 9. The process as claimed in claim 2 in whichthe organo-soluble catalyst used in the preparation of the seeding latexis an organic peroxide catalyst.
 10. The process as claimed in claim 9in which the catalyst is selected from the group consisting of lauroylperoxide, tertiobutyl diethylperacetate, diethylhexylpercarbonate anddiacetyl peroxide.
 11. The process as claimed in claim 2 in which theamount of polymer or copolymer of the seeding latex dispersed with themonomer or comonomer of the polymerizing composition is within the rangeof 2 to 6 percent by weight of the monomer or comonomer of thepolymerizing composition.
 12. The process as claimed in claim 2 in whicha dispersing agent is introduced in the polymerization composition viathe seeding latex, or with the monomer or comonomers into which thelatex is dispersed.
 13. The process as claimed in claim 12 in which thedispersing agent is of the emulsifying type.
 14. The process as claimedin claim 12 in which the dispersing agent comprises a protectivecolloid.
 15. The process as claimed in claim 13 in which the dispersingagent is an anionic agent selected from the group consisting of alkalimetal sulphonates and sulphosuccinates.
 16. The process as claimed inclaim 13 in which the dispersing agent is of a non-ionic type selectedfrom the group consisting of ethylene polyoxide grafted by styrene orvinyl acetate, or a fatty acid polyethoxyester.
 17. The process asclaimed in claim 12 in which the dispersing agent is present in anamount less than 2 percent by weight of the monomeric or comonomericpolymerizing composition.
 18. The process as claimed in claim 12 inwhich the dispersing agent is present in an amount within the range of0.1 to 0.3 percent by weight of the monomer or comonomers of thepolymerizing composition.
 19. The process as claimed in claim 14 inwhich the protective colloid is selected from the group consisting ofmethyl cellulose, polyvinyl alcohol, carboxy cellulose and gelatin. 20.The process as claimed in claim 2 in which the monomers and comonomerspolymerized are selected from the group consisting of vinyl chloride;vinyl chloride and at least one olefin; vinyl chloride and vinylacetate; vinyl chloride, vinyl acetate and at least one olefin; vinylchloride and vinylidene chloride.
 21. The process as claimed in claim 20in which the olefin is selected from the group consisting of ethylene,propylene, butene-1, butene-2, isobutene, and methyl-4-pentene-1. 22.The process as claimed in claim 2 in which an activator is introducedvia the seeding latex or with the monomer or comonomer into which thelatex is dispersed.
 23. The process as claimed in claim 22 in which whenthe activator is introduced via the seeding latex it is selected fromthe group consisting of ammonia, sodium sulphoxylate formaldehyde andsodium metabisulphite and when the activator is introduced with themonomer or comonomer it is selected from the group consisting ofascorbyl palmitate and hydroxymaleic acid.
 24. The process as claimed inclaim 22 in which the activator is used in molar dosages less than 1based upon the catalyst or catalysts of the organo-soluble typecontained in the particles of the seeding latex.
 25. The process asclaimed in claim 2 in which the amount of catalyst contained in theparticles of the seeding latex is sufficient for polymerization of themonomeric or comonomeric materials to a conversion rate in excess of 70percent.
 26. The process as claimed in claim 2 in which the polymerizingcomposition is heated to a temperature within the range of 1* to 90* Cfor polymerization.
 27. The process as claimed in claim 2 in which thepolymerizing composition is heated to a temperature within the range of30* to 70* C for polymerization.
 28. The process as claimed in claim 1in which the polymer is coagulated within the droplets when the polymerparticle content is about 50% by weight.